The Visual System Visual Processing at Retina Graded
- Slides: 54
The Visual System
Visual Processing at Retina § Graded potential VS Action potential
Visual Processing at Retina § Horizontal VS Amacrine
Visual Processing at Retina § Horizontal Lateral inhibition and lateral interactions / maintain sensitivity to luminance contrast § Amacrine § Transform changes in light intensity § Some types are the only pathway to transmits information from photoreceptors to ganglion cells
Visual Processing at Retina § Inhibited Bipolar VS Activated Bipolar
Visual Processing at Retina § Inhibited Bipolar VS Activated Bipolar
Visual Processing at Retina § On Center Ganglionic VS Off center Ganglionic
Ganglionic Cells Subtypes
Y X
Y § Position § Receptive field § Details § movement X
Y § Position § Receptive field § Details § movement W X
Lateral geniculate nucleus
Lateral geniculate nucleus
Lateral geniculate nucleus
Lateral geniculate nucleus
Lateral geniculate nucleus
Magnocellular system Parvocellular system
VISUAL PATHWAY
The retinohypothalamic pathway • day/night cycle • Melanopsin ganglionic cells
Visual Pathways The optic nerve has two principle branches
Primary visual cortex
Ventral “What” pathway
Ventral “What” pathway • Carries information about static object properties such as colour, luminance, stereopsis and pattern recognition. • Slow pathway from P-ganglion cells (through laminae 3 -6 of LGN, V 1) to V 2, V 4 and inferior temporal cortex
Dorsal “Where” pathway
Dorsal “Where” pathway • Information about dynamic object properties- motion and spatial relationships • Fast pathway for transient visual signals • Pathway to V 1, V 2, MT, medial superior temporal and parietal lobe
Optics of Vision Light refraction
Optics of Vision
Optics of Vision Refraction power a lens “Diopter” = 1 m / focal length
Optics of Vision
Optics of Vision
Picture Formation cataracts (opacities in the lens)
Picture Formation • Lens accommodation • Pupil adjustment • Fusion of the two eyes
Optics of Vision
Optics of Vision
Accommodation
Accommodation
Vision problems Ametropia : refraction error, inabiulity of properly focusing light on the retina, a frequent reason for reduced visual acuity
Vision problems
Accommodation Presbyopia: Loss of accommodation by the lens
Accommodation Presbyopia: Loss of lens accommodation by the
Vision problems Astigmatism : irregular curvature of either the cornea or the lens, which lead to blurred or distorted vision due to parts of the image are out of focus.
Accommodation and parasympathetic The pupil near reflex
Pupillary Adjustment
Pupillary Adjustment
- The retina-geniculate-striate system is organized
- The retina-geniculate-striate system is organized
- Label of egg
- Kode icd 10 filled eye
- Special senses physiology
- Cow eye dissection steps
- Iss internet scanner
- Equatore occhio
- Retina layer
- Retina histology
- Camadas da retina
- Boeck candy test
- 10 layers of retina
- Conos y bastones de la retina
- Retinae commotio
- Sheep eye iris
- In sheep eye color is controlled
- Augenheilkunde
- Inherent tone of ciliary muscle
- Retina tu dortmund
- Capas de la retina
- Vertical invertida
- The innermost tunic of the eye
- Retina
- Degenerazione retinica pavimentosa
- Amanah artinya
- Iridial retina
- Intermediate uveitis
- Retina
- Cow eye parts
- Deatched retina
- Retina and optic nerve
- Silver wiring
- øjets anatomi
- Neuroepitelio retina
- Anatomy and physiology of the retina
- Itc. semmelweis
- Retína
- Retina image formation
- Fovea centralis cow eye
- Retina center iasi
- "retina risk"
- Drcr retina network
- Iris retina
- Invecchiamento della retina
- Top-down vs bottom-up processing
- Gloria suarez
- Bottom up and top down processing
- Point processing and neighbourhood processing
- Example of primary processing
- Image enhancement by point processing
- Histogram processing in digital image processing
- Parallel processing vs concurrent processing
- Laplacian filter
- Image processing